[Ragweed in France; some air pollen data for the years 1987-1990].

The permanent recording of air pollen contain from more than 25 sites distributed all over France using the same method gives homogeneous results with every two hours daily measures. Among usual pollen taxa harvested in the city of Lyon, Ambrosia pollen data is to be emphasized due to its high allergenic potency. Between years 1987 and 1990, Ambrosia pollen data observed in Lyon have been recorded and completed with data obtained from other places in France where Ambrosia is also to be found during the summer and autumn seasons. Significant annual variations have been observed while the daily repartition of records appear quite steady. Data obtained do emphasize the high allergenic potency of Ambrosia of air pollen origin in a great number of french regions.